Abstract
Perceived brightness is nonlinearly related to luminance. Consequently, any mechanism operating on the (transformed) luminance profile of a blurred edge to detect its location should make errors, and the magnitude of these errors should increase with contrast. The perceived location of a blurred edge was measured at a range of contrasts and a range of blur space constants in a vernier alignment task. It was found that the perceived location of a blurred edge was affected by the contrast and the blur space constant of the edge. At low contrasts, the apparent location of the blurred edge was near the calculated location of the edge, assuming the linear transduction of luminance. At higher contrasts, the perceived location of a blurred edge was shifted toward the dark side of the edge, and the shift increased with contrast.
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References
Makous, W., Williams, D. R., &Macleod, D.I. A. (1985). Nonlinear transformation in human vision.Journal of the Optical Society of America A,13, P80.
Marr, D., &Hildreth, E. (1980). Theory of edge detection.Proceedings of the Royal Society of London: Series B,207, 187–217.
Mather, G., &Morgan, M. (1986). Irradiation: Implications for theories of edge localisation.Vision Research,26, 1007–1015.
Morrone, C., &Burr, D. (1988). Feature detection in human vision: A phase-dependent energy model.Proceedings of the Royal Society of London: Series B,235, 221–245.
Naiman, A. C., &Makous, W. (1993). Undetected grey strips displace perceived edges non-linearly.Journal of the Optical Society of America A,10, 794–803.
Stevens, S. S., &Galanter, E. M. (1957). Ratio scales and category scales for a dozen perceptual continua. Journal ofExperimental Psychology, 54, 377–411.
Watt, R. J., &Morgan, M. (1983). The recognition and representation of edge blur: Evidence for spatial primitives in vision.Vision Research,23, 1465–1477.
Watt, R. J., &Morgan, M. (1985). A theory of the primitive spatial code in human vision.Vision Research,25, 1661–1674.
Weibull, W. (1951). A statistical distribution function of wide applicability.Journal of Applied Mathematics,18, 292–297.
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This research was supported by SERC and by British Aerospace PLC.
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Bex, P.J., Edgar, G.K. Shifts in the perceived location of a blurred edge increase with contrast. Perception & Psychophysics 57, 1187–1189 (1995). https://doi.org/10.3758/BF03208374
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DOI: https://doi.org/10.3758/BF03208374